function logout(){
    if(confirm("是否确定注销?")){
        //点击了"是"
        //1.销毁session
        jQuery.ajax({
            url:"/user/logout",
            type:"POST",
            data:{},
            success:function(res){}
        });
        //2.跳转到登录页
        location.href="login.html";
    }
    
}